This application claims priority of Taiwanese application no. 091206938, filed on May 15, 2002.
1. Field of the Invention
The invention relates to a scroll saw, more particularly to a scroll saw capable of sawing angle adjustment.
2. Description of the Related Art
Referring to FIGS. 1, 2 and 3, a conventional scroll saw 10 is shown to include a work platform 11, a hollow C-shaped frame 12, a work table 17, a blade unit 166, a blade holder unit 14, a motor unit 13, a transmission unit 15, and a sawing angle adjusting unit 18.
The work platform 11 extends in a longitudinal direction, and has a first end 111 and a second end 112 opposite to the first end 111 in the longitudinal direction. A table support block 113 extends uprightly from the second end 112, and is formed with a pivot hole 114.
The C-shaped frame 12 has an upper frame portion 122, and a lower frame portion 123 mounted fixedly on the work platform 11. The lower frame portion 123 is formed with a pivot hole 121 that is aligned with the pivot hole 114 in the table support block 113.
The work table 17 is disposed on top of the work platform 11, and is formed with a blade slot 171 and a pivot pin 172 inserted into the pivot hole 121.
The blade unit 166 passes through the blade slot 171 in the work table 17, and has upper and lower blade ends.
The blade holder unit 14 includes upper and lower blade holder arms respectively extending above and below the work table 17, and connected to a respective one of the upper and lower blade ends and to a respective one of the upper and lower frame portions 122, 123 of the C-shaped frame 12.
The motor unit 13 is mounted in the C-shaped frame 12. The transmission unit 15 interconnects the motor unit 13 and the blade holder unit 14 to drive the blade holder unit 14 for moving the blade unit 166 to reciprocate relative to the work table 17 to cut a work piece (not shown) on the work table 17.
The sawing angle adjusting unit 18 includes a sawing angle adjusting plate 181 that is mounted on the bottom side of the work table 17. The adjusting plate 181 is formed with a curved slot 1811, angle indica adjacent to the curved slot 1811, and a pivot pin 182 inserted into the pivot hole 114 in the table support block 113. The adjusting unit 18 further includes a threaded fastener 183 extending through the curved slot 1811 and threadedly engaging the table support block 113.
Referring further to FIG. 4, if the work piece is to be cut at an angle, the angle formed between the blade 166 and the work table 17 must be adjusted. To this end, the fastener 183 is first operated to loosen the work table 17 from the work platform 11. A force is then exerted on the work table 17 so as to pivot both the work table 17 and the sawing angle adjusting plate 181 about the pivot pins 172, 182. Upon adjustment to the desired angle, the fastener 183 is once again operated to clamp the adjusting plate 181 against the table support block 113.
The following are some of the drawbacks of the conventional scroll saw 10:
1. Since the sawing angle adjusting unit 18 is located under the work table 17, sawing angle adjustment and reading of the angle indica are inconvenient to conduct.
2. Because the work piece tilts with the work table 17, it is not easy to control the position of the work piece during the sawing operation, thereby resulting in poor work quality and efficiency.
Therefore, the main object of the present invention is to provide a scroll saw that can overcome the aforesaid drawbacks of the prior art.
Accordingly, the scroll saw of the present invention includes:
a work platform having a top side extending and defining a center line in a longitudinal direction and formed with a blade slot transverse to the longitudinal direction;
a C-shaped frame having upper and lower frame portions disposed above and below the top side of the work platform, respectively;
a blade unit passing through the blade slot in the work platform and having upper and lower blade ends;
a blade holder unit including upper and lower blade holder arms respectively extending above and below the top side of the work platform, and connected to a respective one of the upper and lower blade ends and to a respective one of the upper and lower frame portions;
a motor unit mounted on the work platform;
a transmission unit interconnecting the motor unit and the blade holder unit to drive the blade holder unit for moving the blade unit to reciprocate relative to the work platform;
a pivot unit for mounting pivotally the C-shaped frame on the work platform about a pivot axis parallel to the center line, thereby permitting sawing angle adjustment; and
a locking unit for locking releasable the C-shaped frame to the work platform so as to arrest pivoting movement of the C-shaped frame relative to the work platform, thereby permitting retention of the C-shaped frame at a desired sawing angle.